/* 初始化 */
*{
    padding: 0; margin:0; text-decoration: none; list-style: none;
    box-sizing: border-box;
}
body,html{
    height: 100%;
}
body{
    display: flex; flex-direction: column;
}
/* header */
.header{
    height: 50px; background-color: #ccc;
    display: flex; align-items: center; justify-content: center;
}
.main{
    display: flex;
    flex: 1;
    background-color: #fff;
}
.main>.left-nav{
    width: 220px;
}
.left-nav>.operation>h3, .left-nav>.category>h3{
    background: lightskyblue;
    line-height: 41px;
    text-align: center;
    letter-spacing: 2em;
    padding-left: 2em;
}
.left-nav>.operation>ul>li,.left-nav>.category>ul>li{
    height: 26px;
    display: flex; justify-content: center; line-height: 30px;
    color: #002c99; font-weight: 500; cursor: pointer;
}
.main>.content-box{
    flex: 1;
    padding-left: 20px;
    height: 100%;
}
.main>.content-box>.content{
    height: 96%;
}


#layout{
    
}